I. Field of the Invention
This invention relates generally to orthodontic brackets, and more particularly to a fixed functional bracket responsive to differential forces wherein an archwire can slide three dimensionally within the bracket in a low-friction arrangement.
II. Background of the Invention
Orthodontics encompasses the correction of dental irregularities and malocclusions by applying controlled precise forces to teeth. The type of orthodontic mechanism employed is most important because success in orthodontic treatment depends so much on the efficiency of the appliances. Orthodontists who have a high degree of biologic knowledge as well as a high degree of mechanical skill cannot produce the highest standards of treatment unless they employ the most efficient orthodontic mechanism. It is the purpose of this invention to provide such a mechanism. Several methods and mechanisms of orthodontic treatment are typically employed. The focus of this invention evolves from three, namely 1) functional (removable appliance) orthodontics, 2) light wire (fixed bracketed) orthodontics, and 3) edgewise (fixed bracketed) orthodontics. A major goal of a functional appliance is to relieve pressure on teeth and bone associated with oral musculature which allows for expansion and settling of teeth by nature. This happens as teeth occlude. Light wire mechanics offer differential force values. Early pioneers Storey and Smith define optimal orthodontic force value (delivered to a bracketed tooth) as the application of force to move teeth at a most favorable rate and with least tissue damage and pain. Light wire mechanics are generally associated with round wire. They generally allow freedom of three dimensional control (tip, torque, and rotation) by use of auxiliary components as teeth are guided to a predetermined round wire arch grid. Edgewise mechanics are accomplished by turning a rectangular wire on its side so that its edge can be engaged in a rectangular slot engraved into a bracket form. Tooth movement is achieved as three dimensional control (tip, torque, and rotation) is bent into the wire and is subsequently engaged in the rectangular bracket slot. All three methods have merit but lack in totality. Historically attempts have been made by idealists to fabricate appliances according to principals derived from engineering practices that will exert precise values, that is, force values that vary only slightly and within definite limits. These engineering principals cannot be translated without modification to the art of orthodontics. Certain material modifications have now become available that make this possible. Namely nickel titanium, high grade polycarbonate, and a large ceramic family. This invention takes advantage of these state of the art materials and allows a favorable environment as envisioned by Storey and Smith and other orthodontic forefathers and modern day idealists.